Condensed Consolidated Balance Sheets - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents, unrestricted		$ 266,400	$ 105,684
Restricted cash		5,195	4,000
Total cash, cash equivalents and restricted cash		271,595	109,684
Short-term investments		209,391	300,676
Total cash and cash equivalents, restricted cash and short-term investments		480,986	410,360
Student receivables, gross		79,618	84,599
Allowance for credit losses		(37,133)	(39,917)
Student receivables, net		42,485	44,682
Receivables, other		1,900	2,873
Prepaid expenses		8,078	8,209
Inventories		1,178	596
Other current assets		2,517	341
Total current assets		537,144	467,061
NON-CURRENT ASSETS:
Property and equipment, net of accumulated depreciation of $110,648 and $101,380 as of September 30, 2021 and December 31, 2020, respectively		25,838	27,761
Right of use asset, net		38,793	44,773
Goodwill		162,692	118,312
Intangible assets, net of amortization of $6,761 and $4,178 as of September 30, 2021 and December 31, 2020, respectively		34,109	15,522
Student receivables, gross		4,239	3,533
Allowance for credit losses		(2,889)	(2,230)
Student receivables, net		1,350	1,303
Deferred income tax assets, net		30,413	40,351
Other assets		6,080	6,434
TOTAL ASSETS	[1]	836,419	721,517
CURRENT LIABILITIES:
Lease liability-operating		10,036	9,789
Accounts payable		12,650	13,259
Accrued expenses:
Payroll and related benefits		22,764	22,661
Advertising and marketing costs		10,749	10,249
Income taxes		3,565	1,402
Other		17,596	11,921
Deferred revenue		57,051	34,534
Total current liabilities		134,411	103,815
NON-CURRENT LIABILITIES:
Lease liability-operating		37,732	43,405
Other liabilities		18,891	18,390
Total non-current liabilities		56,623	61,795
STOCKHOLDERS' EQUITY:
Preferred stock, $0.01 par value; 1,000,000 shares authorized; none issued or outstanding
Common stock, $0.01 par value; 300,000,000 shares authorized; 87,908,259 and 87,264,910 shares issued, 70,105,521 and 70,062,364 shares outstanding as of September 30, 2021 and December 31, 2020, respectively		879	873
Additional paid-in capital		670,497	658,423
Accumulated other comprehensive (loss) income		(3)	364
Retained earnings		227,506	142,335
Treasury stock, at cost; 17,802,738 and 17,202,546 shares as of September 30, 2021 and December 31, 2020, respectively		(253,494)	(246,088)
Total stockholders' equity		645,385	555,907
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY		$ 836,419	$ 721,517

[1] Total assets do not include intercompany receivable or payable activity between institutions and corporate and investments in subsidiaries.